"A Hush-Hush Topic No More"

On a recent Friday night, a small group of people lined up in a cinder-block hallway inside an unmarked entrance to Paddles, a club on West 26th Street. Two men in their 60s were discussing real estate and a few women in their 20s were sending last-minute texts before going down two flights to the subterranean space.

Paddles is not another trendy table tennis emporium, but a “safe space” to live out erotic fantasies, specifically BDSM (bondage/discipline, domination/submission, sadism/masochism), OTK (over the knee; in other words, spanking), and an alphabet soup’s worth of other sexual practices that, until recently, have gone largely unnoticed and undiscussed by the mainstream world.

But surely in part because of the blockbuster success of E. L. James’s “Fifty Shades of Grey” trilogy (65 million copies sold worldwide according to Publishers Weekly), people who are drawn to power exchange in sexuality and may refer to themselves as kinky are finding themselves in the spotlight as never before.

In February, “kink,” a documentary directed by Christina Voros and produced by James Franco, had its premiere at the Sundance Film Festival. (The Hollywood Reporter called it “a friendly film about lots of seemingly reasonable people who do terrible things to each other on camera for money.”) Phrases like “safe word” are increasingly part of pop culture; on the IFC hit “Portlandia,” one sensitive character said hers (“cacao”) even when her boyfriend is sleeping. On Showtime’s “Shameless,” Joan Cusack plays a kinky mother trying to manage the enthusiasm and pricey toy collection of her younger lover.

And some real-life kinksters — a few of whom are appropriating the epithet “pervert,” much as gay activists seized control of “queer” — are wondering if they are approaching a time when they, like the L.G.B.T. community before them, can come out and begin living more open, integrated lives.

But that time, it seems, has not yet arrived. Though the Harvard Munch Club, a social group of around 30 students focusing on kinky interests, was officially recognized by the university in December, its 21-year-old founding president asked that he not be identified. (“I’m interested in politics,” he offered as one reason.) He said that he had “encountered zero negative responses on campus,” and received messages from alumni expressing solidarity and wishing there had been a similar group when they were undergraduates.

A 20-year-old college student and self-described submissive on Long Island who asked to be referred to only by her middle name, Marie, said that she was disowned by her parents when a partner’s lover outed her as kinky. “They were just beside themselves,” Marie said. “I think they were worried I would get hurt.”

She saw how telling people could be complicated. “It’s like being gay in that it’s a sexual preference, but it’s not like being gay in the sense that it’s not who you love, it’s how you love,” she said, adding, “The coming out is a little bit different.” Still, she said, “among people my own age, I haven’t found anyone who thinks I’m weird or doesn’t want to be friends.”

For those who find hostility in the wider world, though, there are plenty of welcoming environments to be found. Inside Paddles, there are black walls and a mural featuring a cartoon woman in thigh-high red boots standing with a stiletto heel on a man’s back. The bar, called Whips and Licks Cafe, does not sell alcohol, but coffee, sodas and Italian ices, giving the atmosphere an unexpectedly wholesome feeling. Opposite it was a display of paddles, floggers and other equipment for sale. The club’s various nooks and crannies featured rigs, chains, cages and benches where participants could pair up and play out whatever “scenes” they agreed upon.

Tucked away in one room, a man and woman were sharing fire play, which involved accelerant placed on strategic points of the woman’s body and set ablaze in short, dramatic bursts. In another area, decorated to look like a dungeon, a middle-aged man was lashing a middle-aged woman’s bare back with a single tail whip. Intercourse and oral sex are not allowed at Paddles, but many people had their shirts off, mixing comfortably without any apparent self-consciousness.

The crowd was mixed-age and multiethnic, and the mood was friendly and upbeat. If you ignored the occasional yelps and moans and stripped away the exotic gear, it could have been a gathering of any hobby group, albeit one where photos were prohibited and participants mostly used aliases.

“One out of five people these days who come to our events are novices who say they’ve read ‘Fifty Shades’ and it triggered something and they wanted to explore,” said a man identifying himself as Viktor, 49, who works in marketing and is a founder of DomSubFriends, a BDSM education group that organized a lecture on jealousy that night. “In the beginning I thought, ‘They took away my BDSM,’ ” he said of the newbies. “But then I thought, ‘No, more people are enjoying it.’ ”

Fetish shops like Purple Passion/DV8 on West 20th Street, which sell rope, paddles and other accouterments familiar to BDSM aficionados, are also getting more visits. “We always had people coming in looking to explore, but now there’s a lot more people experimenting and trying things out,” said Lolita Wolf, who works behind the counter and teaches classes like beginner rope bondage and how to play with needles at the shop.

For those not ready to explore kink in public, dating sites like Alt.com and social networks like FetLife let them do so from their own homes or mobile devices. Founded in 2008 and based in Vancouver, British Columbia, FetLife added 700,000 members last year, bringing its total membership to over 1.7 million, according to Susan Wright, a community manager for the site as well as a spokeswoman for the National Coalition for Sexual Freedom, a nonprofit group based in Baltimore that is working to raise awareness of kinky people and defend their rights.

It’s understandable that kinky people would seek the anonymous refuge of the Internet; their preferences can be made an issue in custody battles (even if both parents have participated) or contribute to employees losing their jobs. Valerie White, a founder of the Sexual Freedom Legal Defense and Education Fund, a nonprofit advocacy and education group based in Sharon, Mass., points to one man whose ex-wife sought to change the terms of their joint custody when she learned of his interest in kinky sex through his blog (the parties eventually settled).

Ms. Wright said the coalition receives 600 calls a year from individuals and organizations seeking help navigating legal minefields. Founded in 1997, the coalition has lobbied to have the American Psychiatric Association update the definitions of certain sexual practices so they can be depathologized in the Diagnostic Statistical Manual. “We’re perfectly ordinary people except that we like kinky sex,” said Ms. Wright, 49, who is a science fiction writer and has been married 19 years. “We should not be discriminated against.”

The group also maintains a database of “kink-aware” clinicians and spiritual advisers. Some therapists say “something is wrong with you, that it’s a pathology,” said Dr. Charley Ferrer, a clinical psychologist in Manhattan and Staten Island and the author of “BDSM: The Naked Truth.” (That perception is reinforced by the “Fifty Shades’” protagonist, Christian Grey.) “Most people look at BDSM as being abusive: ‘How can you tell someone to beat you and be happy with that?’ Domestic violence and dominance and submission are totally different.” ...